Disposable Condenser Dosimeter Using a Skin-Insulated Mini-Substrate with a Silicon X-Ray Diode in Image-Guided Radiation Therapy

• 作者: Eiichi Sato Hirobumi Oikawa Hisanori Ariga Hisao Kakuhara Koyo Kikuchi Ryuji Nakamura Satoshi Yamaguchi Shigeru Ehara
• 来源期刊: 医学物理学、临床工程、放射肿瘤学(英文)
• 学科: 医学
• 关键词: CONDENSER DOSIMETER DISPOSABLE Mini-Substrate Surface
• 年，卷（期）: 2018,（1）
• 页码范围: 35-46
• 页数: 12页
• 分类号: R73

摘要

To measure integral doses in image-guided radiation therapy, we developed a disposable mini-substrate with a 1.0-μF condenser and a silicon X-ray diode (Si-XD). The Si-XD is a high-sensitivity photodiode selected for detecting X-rays. In the substrate with dimensions of 15 × 15 mm2, the initial charging voltage is 3.30 V, and the charging voltage is decreased by photocurrents flowing through the Si-XD during X-ray exposing. The condenser in the substrate is charged by a microcomputer dock, and the charging voltage is also measured using an analog to digital converter in the dock after exposing X-rays. The dock is connected to a personal computer through a USB cable, and integral doses are shown on the PC monitor. The doses were proportional to decreases in the charging voltage, and the calibrated doses corresponded well to those obtained using a readily available ionization chamber.